1 files changed, 58 insertions, 0 deletions
diff --git a/lib/PublicInbox/DSPoll.pm b/lib/PublicInbox/DSPoll.pm
new file mode 100644
index 00000000..e65640a8
--- /dev/null
+++ b/lib/PublicInbox/DSPoll.pm
@@ -0,0 +1,58 @@
+# Copyright (C) 2019 all contributors <meta@public-inbox.org>
+# Licensed the same as Danga::Socket (and Perl5)
+# License: GPL-1.0+ or Artistic-1.0-Perl
+#  <https://www.gnu.org/licenses/gpl-1.0.txt>
+#  <https://dev.perl.org/licenses/artistic.html>
+#
+# poll(2) via IO::Poll core module.  This makes poll look
+# like epoll to simplify the code in DS.pm.  This is NOT meant to be
+# an all encompassing emulation of epoll via IO::Poll, but just to
+# support cases public-inbox-nntpd/httpd care about.
+package PublicInbox::DSPoll;
+use strict;
+use warnings;
+use parent qw(Exporter);
+use IO::Poll;
+use PublicInbox::Syscall qw(EPOLLONESHOT EPOLLIN EPOLLOUT EPOLL_CTL_DEL);
+our @EXPORT = qw(epoll_ctl epoll_wait);
+
+sub new { bless {}, $_[0] } # fd => events
+
+sub epoll_ctl {
+        my ($self, $op, $fd, $ev) = @_;
+
+        # not wasting time on error checking
+        if ($op != EPOLL_CTL_DEL) {
+                $self->{$fd} = $ev;
+        } else {
+                delete $self->{$fd};
+        }
+        0;
+}
+
+sub epoll_wait {
+        my ($self, $maxevents, $timeout_msec, $events) = @_;
+        my @pset;
+        while (my ($fd, $events) = each %$self) {
+                my $pevents = $events & EPOLLIN ? POLLIN : 0;
+                $pevents |= $events & EPOLLOUT ? POLLOUT : 0;
+                push(@pset, $fd, $pevents);
+        }
+        @$events = ();
+        my $n = IO::Poll::_poll($timeout_msec, @pset);
+        if ($n >= 0) {
+                for (my $i = 0; $i < @pset; ) {
+                        my $fd = $pset[$i++];
+                        my $revents = $pset[$i++] or next;
+                        delete($self->{$fd}) if $self->{$fd} & EPOLLONESHOT;
+                        push @$events, [ $fd ];
+                }
+                my $nevents = scalar @$events;
+                if ($n != $nevents) {
+                        warn "BUG? poll() returned $n, but got $nevents";
+                }
+        }
+        $n;
+}
+
+1;